[Bug tree-optimization/23940] SSA_NAMEs are not released after no longer being used.

["pinskia at physics dot uc dot edu" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From pinskia at physics dot uc dot edu  2005-09-19 16:05 -------
Subject: Re:  SSA_NAMEs are not released after no longer being used.


On Sep 19, 2005, at 11:59 AM, amacleod at redhat dot com wrote:

> We also probably have to set SSA_NAME_DEF_STMT to NULL in bsi_remove 
> in order to
> be sure that an SSA name with no uses isn't actually associated with a 
> stmt any
> more (you can have valid defs with no uses). It is set when the 
> SSA_NAME is
> created, but I don't think that field ever gets cleared anywhere else.

Except that does not work as mentioned before as people do bsi_remove
and then bsi_insert on the same staement when moving the statement 
around.
And isn't that the same thing as adding release_defs in bsi_remove?

And that will not work for the SSA_NAMEs used for aliasing and then the
variable becomes a gimple register.


-- Pinski



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23940